You tell children that in our country we have a very important law, and that law says you can't discriminate against people on the basis of their sexual identity.
Sanderijn van der Doef, Dutch child psychologist

When Ms. van der Doef reads these books to audiences of four- and five-year-olds, she says, they stare up at her with big eyes, hanging on her every word. A sense of embarrassment about sex develops only later, she says, when children are 7 or 8. At that age, they will often laugh when she talks about same-sex relationships.

“I explain that it's nothing to laugh about, it's normal,” she says. “I'm very convinced that if you start talking about it early, that you normalize homosexuality for children.”

This, of course, is the problem for some parents. As Mr. McVety puts it, “I doubt you could get 10 parents in a room that would agree to teach their eight-year-old ‘gender identity.' There's no way the majority of parents in this province are going to agree.”

But Ms. van der Doef said religious objections toward same-sex relationships have been addressed in the Netherlands at a legislative level. “You tell children that in our country we have a very important law, and that law says you can't discriminate against people on the basis of their sexual identity,” she says. “You don't have to agree with it personally, but you have to respect it in your behaviour.”

In 2009, the United Nations Educational, Scientific and Cultural Organization (UNESCO) introduced international guidelines for sexual education that recommended children learn about sexual health and identity beginning at the age of 5, and receive more detailed information starting at 9.

“When they published these guidelines, they got so much protest and resistance, especially about explaining masturbation to young children,” Ms. van der Doef says. “But they kept it in.”

Alex McKay, research co-ordinator for the Sex Information and Education Council of Canada, believes it is better to use the word “masturbation” than to rely on euphemisms. “Masturbation is very common during puberty. I'm not sure there's any benefit in pretending it doesn't occur,” he says. “Knowledge is preferable to ignorance.”

This is the attitude Melanie Frost has applied to her kids' sexual education.

Her eldest daughter, 11-year-old Sara, began her first real sex-ed course this week in her Grade 4 classroom and has already learned about anatomy, reproduction and safe sex.

“I feel much better knowing that the kids will have the facts,” Ms. Frost says. “The sooner they start learning, the better.”

So what did she say when her four-year-old informed the grocery store where babies emerge?